The present invention relates generally to an air-permeable and water-permeable rubber and a method for producing the same.
One conventional technique for producing the air-permeable and water-permeable rubber having a porous structure includes steps of:
(a) adding a large amount of an inorganic salt, such as NaCl, into a raw rubber material; PA1 (b) shaping the rubber material containing the inorganic salt in a mold to form an intermediate product; and PA1 (c) dissolving the inorganic salt in the PA1 (a) Because the present rubber is a porous vulcanized rubber obtained by combining a semi-vulcanized powder with an unvulcanized plastic powder, the strength thereof is excellent because of the high degree of compatibility of the powders. PA1 (b) Because the final product is formed from the semi-vulcanized powder, the distribution of the pores in the final product is uniform and the pores are open, i.e., intercommunicable (as shown in the Figure). Thus, the final product possesses excellent permeability. PA1 (c) The density of the final product can be adjusted as desired and controlled by the mold compressibility and the thickness washer.
intermediate product in water to obtain the final product. Unfortunately, this technique is troublesome and time consuming and therefore is not practical.
Another conventional technique for producing the air-permeable and water-permeable rubber having a porous structure includes steps of: grinding a waste rubber into powder or particles and mixing the powder or particles with an adhesive to bind the powder or the particles to form a porous structure. In this technique, the powder or particles only serve as a filler, and therefore the final product has different pore sizes, it is not uniform and fine, and its elasticity and softness do not meet the required specifications. It is therefore desirable to form a water- and air-permeable rubber which does not have the deficiencies of the prior art.